Question

a scooter is moving with a velocity of 25m/s and it takes 5sec to stop after the brakes are applied if the mass of the scooter along with the rider is 180kg then find the change in momentum

Answer 1

initial momentum P =m×u
=180×25=4500kgm/s
final momentum =m×v
180×0(v=0,as brakes are applied)
0kgm/s
Change in momentum=4500-0=4500kgm/s

Answer 2

u=25 m/s                      

v = 0

t=5 s

m =180 kg

p1  =mu = 180 x 25

             =4500 kg m/s  

p2 = mv = 180 x 0 = 0 kgm/s

          p1 - p2 = 0 - 4500

                      = -4500 kgm/s